TPS2115: Voltage output when IN1 is open

Hello Ishiwata-san,

I will try to recreate this in the lab using the TPS2115 EVM. I will be in touch by EOD Wednesday 7/28/21.

Regards,

Kalin Burnside

Hello Kalin-san,

Thank you for your support.
I am waiting for your reply.

Best Regards,
Ishiwata

Hello Ishiwata-san,

I apologize but I wasn't able to get into the lab today. I'll be able to first thing tomorrow morning.

Regards,

Kalin Burnside

Hello Kalin-san,

I look forward to hearing from you.

Best Regards,
Ishiwata

Hello Kalin-san,

Thanks for your answers and for checking the behavior in the lab.

There was an additional question from the customer.

　-When the conditions are reversed, that is, IN2 is floated. Enter in IN1.
　 In this case as well, does IN2 cross-conduce in the same way?

   -Are there any methods or measures to stop the voltage rise of the floating terminal of this cross-conduction?

Best Regards,
Ishiwata

Hello Ishiwata-san,

You're welcome! 

The event should happen if IN2 is open, while IN1 has a voltage applied.

Is that input going to remain open or is there a certain condition where it will be open and other conditions where it's not? 

Regards,

Kalin Burnside

Hello Kalin-san,

Thanks for your reply.

Normally, IN1 is connected to another power supply.
This time, the power supply of IN1 was not input, and when the power supply of IN2 was input, the voltage was confirmed from IN1.
I opened IN1 to isolate the cause.

Are there any methods or measures to stop the voltage rise of IN1 terminal of this cross-conduction?

Best Regards,
Ishiwata

Hello Ishiwata-san,

One possible way to prevent this would be to add a diode. We also have a more recent device that doesn't have this behavior- TPS2116; however, you will need to check to make sure it fits your application. 

Regards,

Kalin Burnside